Power toothbrushes and other personal care appliances typically include a user interface panel which provides for user control of, and associated indications of, various operating modes of the appliance. For example, a power toothbrush can include several different cleaning modes involving different brushhead speeds and/or amplitudes, and further could have various sequences of different modes for a set brushing time, e.g. two minutes. A control button or other user interface is usually provided for selecting a particular mode, and the panel indication of the selected mode is typically illuminated or otherwise highlighted to provide a clear indication to the user of the mode in which the toothbrush is operating. This allows the user to quickly see in which mode the device is currently operating, and provides the user with the ability to quickly change from one mode to another mode.
Some appliances comprise a hidden interface panel, also referred to as a dead panel. With such panels, when the appliance is off, the panel is completely blank. When the appliance is on, the panel is visible with the one or more mode indications. Although this adds to the attractiveness of the appliance, hidden panels are structurally complex and require a number of different parts. As result, hidden panels are more expensive and time-consuming to manufacture. Additionally, when a hidden panel is painted or colored and subsequently illuminated with light during use, the light can produce hot spots where the center of the light is brighter than the outside edges of the light. This bleed-through or hot spot illumination detracts from the utility and visual appeal of the panel.
Accordingly, there is a continued need in the art for methods and devices with hidden panels that are affordable and less time-consuming to manufacture, and avoid bleed-through or hot spot illumination.